Stage III non-small cell lung cancer (NSCLC) is the most difficult and challenging lung cancer to diagnose and treat. According to the 8th edition of AJCC staging, stage III NSCLC is divided into stage IIIA, IIIB and IIIC. Stage IIIA includes cases such as T4N0M0, T3N1M0, T4N1M0, T1N2M0 and T2N2M0, stage IIIB includes cases such as T3N2M0, T4N2M0, T1N3M0 and T2N3M0, and stage IIIC includes cases such as T3N3M0 and T4N3M0. ①Considering that the treatment of stage III NSCLC is very complicated, the diagnosis and treatment of stage III NSCLC requires comprehensive treatment by a multidisciplinary team including at least thoracic surgery, medical oncology, radiation oncology, imaging, etc., to select patients who can be operated. ② From the staging point of view, patients with stage IIIA and some stage IIIB of N2 may receive surgical treatment, and patients with stage IIIB and IIIC of N3 are not recommended to receive surgical treatment. (③Stage IIIA NSCLC judged clinically to be completely surgically resectable includes lesions with T4N0M0, T3N1, and partial T4N1 (such as direct tumor invasion of the chest wall, main bronchus, or mediastinum) with or without single-station mediastinal lymph node metastasis. For this group of patients, surgical resection and postoperative adjuvant chemotherapy with a platinum-containing two-drug regimen are recommended first; for T3 lesions with multiple lesions in the same lobe and T4 lesions with multiple lesions in different lobes of the same lung, the recommended treatment is lobectomy or total pneumonectomy with postoperative adjuvant chemotherapy. (4) Localized invasion of the chest wall without postoperative radiotherapy is controversial. ④ Supraglottic sulcus tumor with local invasion of the chest wall but no mediastinal lymph node metastasis (T3N1). The current recommended treatment is complete surgical resection after neoadjuvant concurrent radiotherapy, with a 2-year survival rate of 50-70% and a 5-year survival rate of 40%. For stage IIIA NSCLC that cannot be directly resected with R0, the basic strategy is radical concurrent radiotherapy; other treatment strategies are neoadjuvant followed by evaluation to decide whether to give complete resection or continue radiotherapy to the radical dose. ⑤ For N2 patients with mediastinal lymph node metastases, the patients were further subdivided according to the mediastinal lymph nodes: a incidental N2 metastases on final pathology of the resected specimen; b single station lymph node metastases found intraoperatively; c single or multiple station lymph node metastases found by preoperative staging (mediastinoscopy, other lymph node biopsy or PET/CT); d giant or fixed multiple station N2 lymph node metastases (CT scan lymph nodes with a short diameter >2 cm on the map). Overall, surgery is recommended in both cases a/b, it is controversial whether c is acceptable for surgery, and d is not recommended for surgery. ⑥After complete tumor resection in patients with EGFR mutation-positive stage III NSCLC, adjuvant therapy with oseltinib (Class 1A evidence), gefitinib (Class 1B evidence), erlotinib (Class 1B evidence) or erlotinib (Class 2 evidence) can be considered, and adjuvant therapy with oseltinib is preferentially recommended. (⑦Postoperative adjuvant immunotherapy, postoperative patients with stage IIIA/B non-small cell lung cancer, following platinum-based chemotherapy, testing to assess tumor cells staining positive for PD-L1 ≥ 1% patients are recommended for atelelizumab monotherapy maintenance treatment. (8) The 5-year survival rates for stage III NSCLC reported by the International Association for the Study of Lung Cancer in 2017 were 41% for stage IIIA, 24% for stage IIIB, and 12% for stage IIIC. The 5-year recurrence rate for patients with operable stage III NSCLC was 76%. The time to recurrence and survival of lung cancer after surgery are closely related to several aspects such as whether the surgery is standardized, whether the staging is standardized, whether the postoperative treatment is standardized, the general condition of the patient, the type of postoperative pathology, the degree of differentiation and genetic status.